The present invention relates to a wheel axle suspension of a vehicle such as a lorry or a trailer. Such a wheel axle suspension typically comprises a tubular wheel axle which is attached to so called trailing arms that are hingedly mounted to the vehicle chassis. Furthermore pneumatic springs are present which are operational between each of the trailing arms and the vehicle chassis.
In DE 296 15 286 a wheel axle suspension is disclosed in which the tubular axle body has a circular cross section and has attachment regions where the axle body is clamped to the trailing arms. The known axle body is deformed in the attachment zones to a non-circular shape. In particular each of the attachment zones is provided with one or more flattened regions in the circumference of the axle body in order to prevent changes in position of the axle body with respect to the trailing arm or a clamping element mounted against the trailing arm.
Vehicles like lorries and trailers provided with air sprung suspensions comprising trailing arms are susceptible to roll movements. The roll movements of the vehicle result in torsional loads on the axle body in the attachment regions thereof. Axle bodies with flattened sides are disadvantageous when considering the strength of the axle body to resist torsional loads.
In U.S. Pat. No. 1,906,290 a different type of wheel axle suspension is disclosed with a stack of leaf springs instead of a trailing arm. In this wheel axle suspension the axle body is flattened in an attachment region on an upper side. The flattened side of the attachment region is mounted against a flat leaf spring or a flat spring saddle. On the opposite side of the attachment region an indentation is provided. A clamp is tightened from below against the axle body, which clamp has a ridge fitting within the indentation. The flattened side and the indentation have for an object to prevent the rotational and longitudinal movement of the mounted axle body.
The present invention has for an object to provide an improved wheel axle suspension which is easy to manufacture and assemble and furthermore is universally applicable.